[review,v2] Use ctime_r and localtime_r if available
Commit Message
Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/475
......................................................................
Use ctime_r and localtime_r if available
To make these calls threadsafe.
gdb/ChangeLog:
2019-10-31 Christian Biesinger <cbiesinger@google.com>
* config.in: Regenerate.
* configure: Regenerate.
* gdbsupport/common.m4: Check for ctime_r.
* configure.ac: Check for localtime_r.
* maint.c (scoped_command_stats::print_time): Use localtime_r
when available instead of localtime.
* nat/linux-osdata.c (time_from_time_t): Use ctime_r if available
instead of ctime.
gdb/gdbserver/ChangeLog:
2019-10-31 Christian Biesinger <cbiesinger@google.com>
* config.in: Regenerate.
* configure: Regenerate.
Change-Id: I329bbdc39d5b576f51859ba00f1617e024c30cbd
---
M gdb/config.in
M gdb/configure
M gdb/configure.ac
M gdb/gdbserver/config.in
M gdb/gdbserver/configure
M gdb/gdbsupport/common.m4
M gdb/maint.c
M gdb/nat/linux-osdata.c
8 files changed, 26 insertions(+), 6 deletions(-)
Comments
On Nov 02 2019, Christian Biesinger (Code Review) wrote:
> diff --git a/gdb/nat/linux-osdata.c b/gdb/nat/linux-osdata.c
> index 67f9f3a..e0bad81 100644
> --- a/gdb/nat/linux-osdata.c
> +++ b/gdb/nat/linux-osdata.c
> @@ -912,7 +912,13 @@
> {
> time_t t = (time_t) seconds;
>
> - strncpy (time, ctime (&t), maxlen);
> + char buf[30];
> +#ifdef HAVE_CTIME_R
> + const char *time_str = ctime_r (&t, buf);
> +#else
> + const char *time_str = ctime (&t);
> +#endif
buf is unused if !HAVE_CTIME_R.
Note that both ctime and ctime_r are obsolescent and should be replaced
by strftime. gdb currently doesn't setlocale LC_TIME, but if it does it
would make the use of these functions undefined.
Andreas.
On Sun, Nov 3, 2019 at 2:20 AM Andreas Schwab <schwab@linux-m68k.org> wrote:
>
> On Nov 02 2019, Christian Biesinger (Code Review) wrote:
>
> > diff --git a/gdb/nat/linux-osdata.c b/gdb/nat/linux-osdata.c
> > index 67f9f3a..e0bad81 100644
> > --- a/gdb/nat/linux-osdata.c
> > +++ b/gdb/nat/linux-osdata.c
> > @@ -912,7 +912,13 @@
> > {
> > time_t t = (time_t) seconds;
> >
> > - strncpy (time, ctime (&t), maxlen);
> > + char buf[30];
> > +#ifdef HAVE_CTIME_R
> > + const char *time_str = ctime_r (&t, buf);
> > +#else
> > + const char *time_str = ctime (&t);
> > +#endif
>
> buf is unused if !HAVE_CTIME_R.
Thanks, fixed.
> Note that both ctime and ctime_r are obsolescent and should be replaced
> by strftime. gdb currently doesn't setlocale LC_TIME, but if it does it
> would make the use of these functions undefined.
I read through the manpage for ctime/ctime_r and I don't see any note
that the behavior is undefined when setlocale is called, or that it is
obsolete. For completeness, I also looked at the Solaris manpage and
it does not say that either. Instead, it will use a locale-independent
format, which seems desirable here since it is serialized into XML.
Christian
@@ -78,6 +78,9 @@
/* Define to 1 if you have the `btowc' function. */
#undef HAVE_BTOWC
+/* Define to 1 if you have the `ctime_r' function. */
+#undef HAVE_CTIME_R
+
/* Define to 1 if you have the <cursesX.h> header file. */
#undef HAVE_CURSESX_H
@@ -261,6 +264,9 @@
/* Define to 1 if you have the <locale.h> header file. */
#undef HAVE_LOCALE_H
+/* Define to 1 if you have the `localtime_r' function. */
+#undef HAVE_LOCALTIME_R
+
/* Define to 1 if the compiler supports long double. */
#undef HAVE_LONG_DOUBLE
@@ -13073,7 +13073,7 @@
sigaction sigsetmask socketpair \
ttrace wborder wresize setlocale iconvlist libiconvlist btowc \
setrlimit getrlimit posix_madvise waitpid \
- ptrace64 sigaltstack setns use_default_colors
+ ptrace64 sigaltstack setns use_default_colors localtime_r
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -13480,7 +13480,7 @@
for ac_func in fdwalk getrlimit pipe pipe2 socketpair sigaction \
- sigprocmask strerror_r
+ sigprocmask strerror_r ctime_r
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -1318,7 +1318,7 @@
sigaction sigsetmask socketpair \
ttrace wborder wresize setlocale iconvlist libiconvlist btowc \
setrlimit getrlimit posix_madvise waitpid \
- ptrace64 sigaltstack setns use_default_colors])
+ ptrace64 sigaltstack setns use_default_colors localtime_r])
AM_LANGINFO_CODESET
GDB_AC_COMMON
@@ -21,6 +21,9 @@
/* Define to 1 if you have the <arpa/inet.h> header file. */
#undef HAVE_ARPA_INET_H
+/* Define to 1 if you have the `ctime_r' function. */
+#undef HAVE_CTIME_R
+
/* define if the compiler supports basic C++11 syntax */
#undef HAVE_CXX11
@@ -6822,7 +6822,7 @@
for ac_func in fdwalk getrlimit pipe pipe2 socketpair sigaction \
- sigprocmask strerror_r
+ sigprocmask strerror_r ctime_r
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -33,7 +33,7 @@
dlfcn.h)
AC_CHECK_FUNCS([fdwalk getrlimit pipe pipe2 socketpair sigaction \
- sigprocmask strerror_r])
+ sigprocmask strerror_r ctime_r])
AC_CHECK_DECLS([strerror, strstr])
@@ -1039,7 +1039,12 @@
auto millis = ticks % 1000;
std::time_t as_time = system_clock::to_time_t (now);
+#ifdef HAVE_LOCALTIME_R
+ struct tm buf;
+ struct tm *tm = localtime_r (&as_time, &buf);
+#else
struct tm *tm = localtime (&as_time);
+#endif
char out[100];
strftime (out, sizeof (out), "%F %H:%M:%S", tm);
@@ -912,7 +912,13 @@
{
time_t t = (time_t) seconds;
- strncpy (time, ctime (&t), maxlen);
+ char buf[30];
+#ifdef HAVE_CTIME_R
+ const char *time_str = ctime_r (&t, buf);
+#else
+ const char *time_str = ctime (&t);
+#endif
+ strncpy (time, time_str, maxlen);
time[maxlen - 1] = '\0';
}
}